Projection key decoding and testing device



June 13, 1950 E. O'BRIEN PROJECTION KEY mzconmq AND TESTING DEVICE Filed Feb. 8, 1946 2 Sheets-Sheet l 'IIIllllIIlIlIIl/III gwue/wbom N E R O E N E G U E June 13, 1950 E. O'BRIEN, 2,510,998

PROJECTION KEY DECODING AND TESTING DEVICE Filed Feb. 8, 1946 2 Sheets-Sheet 2 VERTICAL I5 20 25 3 0 3s 4p 45 so 5 5 so 65 7o 1; ap e5 99 9 5 19019 42.0 1 39.0 AA 35.5 4) J 32.5 E30 J g 50.0 r325 5 IO I5 5O 6O 7O 8O 9O I00 anew m3 Patented June 13, 1950 PROJECTION KEY DECODING AND TESTING VICE Eugene OBrien, Philadelphia, Pa.

Application February 8, 1946, Serial No. 646,472

(Granted under the act of March 3, 1883, as amended April 30, 1928; 370 0. G. 757) 1 Claim.

The present invention relates to means for the determination of cuts on keys, to what key group the key in question belongs, and the accuracy of the cuts in question.

An object of the invention is to determine the classification or identification of keys according to lock group.

Another object is to determine the cuts of a key which are indicated by the number or code it bears, the meaning of which was not previously known to the operator.

A further object is to enable the operator to more easily determine whether or not a given lock may be keyed by cutting according to a code sheet already in his possession but bearing different identification mark or marks than the lock or key.

Another object is to enable the operator to accurately manufacture patterns for key cutting.

Another object is to enable the operator to decode and list, for future key cutting operations, the combinations cut on keys in his possession for which he does not have a code sheet.

A further object is to check the accuracy in spacing and depth of cuts as predetermined for a given key.

Other objects and advantages of the invention will be made apparent in the following description having reference to the accompanying drawings, which are exemplary, and in which:

Fig. 1 is a sectional elevation of an apparatus according to the invention;

Fig. 1a is a projected plan view of the grid l2 of Fig. 1, showing the key of Fig. 3 projected thereon;

Fig. 2 is a front elevation of the apparatus of Fig. 1;

Fig. 3 is a sectional plan view substantially on the line 33 of Fig. l;

Fig. 4 is a view of a master grid film according to the invention;

Fig. 5 is a View of an individual group grid film; and

Fig. 6 is a view of a key which is the subject of the magnified picture of Fig. 5.

In naval and other establishments large numbers of locks are used. In the past it has been necessary to key such locks by hand in the event of key loss, when no key cutting data was available and when manufacturers, when contacted, were unable to furnish the required data.

Referring to the drawings which show means and methods according to the present invention, the apparatus shown in Figs. 1, 2 and 3, comprises a box of wood or other suitable material containing a light projection arrangement which throws an enlarged shadow of the key upon a screen bearing the identifying marks of key groups. Each lock group has a screen which is inserted into a slide in the proper location. The key is inserted into a movable focusing holder. Any

2 discrepancy in the cuts of the keys will be shown both vertically and horizontally. A key without a number can be identified by casting its shadow upon the screen of the group to which the key belongs.

A key G, about which information may be desired, is placed in its proper location on the glass plate 1, against the vertical locating anvil 15, against the adjustable horizontal locating stop l6, and secured in place by the spring-metal clip [4. Access for this purpose is obtained through the swinging shield 5 of the box or housing.

A bulb 2 and junction box I are shown depending from the top of the box. Light issues from the bulb 2, passes through the water cell 3, where the rays are cooled. From there the light passes through the condenser lens 4, where the rays are collected and paralleled. The parallel ray then pass around the key 6, and through the glass plate 1. Parallel rays thus passing create an exact image of the key 6, which image is within the inspection field of the objective lens 8.

The rays conveying the image in process of enlargement then pass through the opening in the stop 9, Where undesirable elements are filtered out. From the stop 9, the rays in process of enlargement proceed onto the first surface mirror l0, where the rays are reflected and the enlarged image received by the ground-glass surface [3. The image is then visible from the opposite side of the ground-glass as a clear cut enlargement with a light background. The ground side of the glass is disposed to be adjacent to the film grid I2.

The picture is then scanned by the operator against an overlay furnished by placing in position the film grid screen l2, held in place by the cover glass l I.

If the group classification is desired, the first reading of the projected picture or image, for example of the key shown in Fig. 6, will be on the master film grid screen, as shown in Fig. 4. Readings are taken on the horizontal lines at the low points of the cuts, and on the vertical lines at the center lines of the cuts.

The readings thus acquired are compared with the readings tabulated according to lock groups on the master grid reference sheets, as illustrated for example in the following:

Group No. Nos. representing cuts Master Grid ggg glggg (as used in code books) iftgirdzlgrgsg Center Line of Cut 42 1st from left, 19.5 38 2nd from left, 32.0 35. 5 3rd from left, 45.0 32. 5 4th from left, 57.5 30 5th from left, 70.0

Use Grid N0. for decoding; Depth keys No. for cutting If it is established that the readings of the picture or image of the key projected on the master grid, coincide with or fall within tabulated readings of any group listed in the master grid reference sheet, such as that shown above, it can be concluded that the key belongs to that look group.

The information thus acquired from the master grid reference sheet thus directs the operator to the use of an individual group grid, such, as shown, for example, in Fig. 5, for use in decoding that group. Each lock group listed in the master grid reference sheet has a corresponding individual group grid.

The operator then replaces the master grid, Fig. 4, by the individual group grid, Fig. 5.

When the individual group grid, Fig. 5, is properly in place with the picture of the key projected thereon, the operator may proceed to decode or identify the key, reading the numbers at the ight hand end of the horizontal lines as they coincide with the low point of the cut of the projected picture of the key, proceeding from left to right on the screen. (Proceeding from the shoulder stop on the key except in cases where it is known that the reverse procedure is necessary.)

Once the cut numbers have been determined, the operator refers to his code books under the lock group to which the grid he has used belongs. Looking opposite the number used as identification, he refers to the code sheets of that group until he either establishes that he has or has not a code sheet listing a lock of that number with cuts as read on the individual group grid, Fig. 5.

If it is so listed, it is likely that the remainder of the series of locks or keys in question will agree With the code sheet, even though the prefix letters may be entirely different or absent. The operator may then check further.

If the operator has a series of locks and the keys which operate them, but not the key cutting data, or code sheets and cutting patterns, and if such data and equipment are desired, it can be obtained by (a) Using the master grid, Fig. 4, to determine at what points the cuts have been made on a series of the keys, thus establishing the theoretical basis for key cutting for that series. If he finds that he has no patterns that conform to the theoretical depths and spacings which the device show to eXiSt on the keys, he may cut them by using the degree of magnification as a gauge of size and then test them by checking on the original readings in the device.

te grid reference sheet, for future use. He

then makes an individual group grid, similar to that in Fig. 5, to suit the needs of the new lock group as to depths and spacings.

Proceeding as previously, he places the individual group grid, decodes the keys and tabulates the lock numbers and corresponding cuts for future use in conjunction with the pattern he has already made.

If a key has been cut to operate a specific lock, and the theoretical cuts are known, but the key will not operate the lock, to check the key proceed as follows:

(a) Place in position the individual group grid. (b) Place in position the key 6.

He then tabulates the readings onto the mas- 4 (0) Read as for decoding, checking the depths and spacings for accuracy.

If it is off, the amount can be gauged accurately from the magnification ratio. Alter the key until it reads correctly and if the lock is in proper working condition the key will operate it.

It will be understood that various changes and modifications may be made in means exemplifying the invention, without departing from the spirit and scope of the invention which is not to be limited other than by the terms of the appended claims.

The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

I claim:

In apparatus for key decoding and testing, a housing, means for receiving a key, means for projecting an enlarged picture or image of the key, a master grid film constructed to be removably mounted in said housing for receiving the projected picture or image of the key, said master grid film being provided with markings enabling the operator to take readings of the configuration or cuts of the projected image of the key for decoding or identifying the key, the means for projecting a picture or image of the key comprising a light source in the top of the housing, a water cell beneath the light source, a condenser lens beneath the water cell, a substantially horizontal glass plate beneath the lens for receiving and supporting a key, means for holding the key in position in the path of the light, said key holding means comprising a vertical locating anvil, an adjustable horizontal locating stop, and a springmetal clip adapted to engage and hold the key, said housing having an opening therein providing for access to said key holding means, a door closing said opening, an objective lens beneath the glass plate, a stop having an opening, a mirror, a ground glass supported in the housing in position to receive the projected image from said mirror, said ground glass having its ground side adjacent to the film and supporting the film, and a cover glass overlying the film, and individual grid films each bearing markings comprising figures and crossing vertical and horizontal lines indicating cuts on keys of a certain lock group, said individual grid films being constructed to removably replace the first-named master grid film in the apparatus and to receive the projected image of the key for decoding or identifying the key as belonging to a certain lock group.

EUGENE OBRIEN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,703,933 Hartness et al Mar. 5, 1929 2,192,529 Thomas et a1. Mar. 5, 1940 2,214,376 Kurz Sept. 10, 1940 2,261,772 Longfellow Nov. 4, 1941 2,313,639 Hauser Mar. 9, 1943 2,380,567 Yawitz July 31, 1945 2,387,210 Wood et al Oct. 16, 1945 2,391,999 Portman et al Jan. 1, 1946 

